Method of coating sheet metal can ends



Dec. 26, 1939. A. L. KRONQUEST METHOD OF COATING SHEET METAL CAN ENDS Filed Nov. '7, 1936 SAMESURFACE 5/[6'17 ll lllll 1 I Illlvllll III INVENTOR.

ATTORNEYS Patented Dec. 26, 1939 Alfred L. Kronquest, Syracuse, N. 1., assignor to Continental Can Company,

Inc., New York,

N. Y., a corporation of New York Application November 7, 1936, Serial No. 109,765

1 Claim.

The invention relates to new and useful improvements in a method of coating a can end which is of sheet metal and adapted to be joined to a can body by rolling parts of the end and 5 body into a seam. It is a well-known expedient to provide a can end with a channel at the peripheral edge portion thereof and apply to said channel a plastic coating material, and then to roll the edge portion of the end and a flange on the can body into a seam. The plastic sealing material will flll all voids and irregularities in the metal and produce an hermetically sealed loint.

An object of the invention is to provide a novel method of applying the coating material to the can end wherein the can ends are caused to travel along a predetermined path and are progressively engaged by a suitable coating applicator without interruption of their continuous travel.

'20 A further object of the invention is to provide a method of the above type which is particularly adapted for applying a coating material to a can end having parallel sides and rounded corners.

In the drawing Figure l is a view in vertical section showing more or less diagrammatically an apparatus for carrying out the invention;

Fig. 2 is a plan view of the same with the conveyor chain omitted and the conveyor lug carried thereby sectioned;

Fig. 3 is a sectional view through a portion of a can body and can end showing the parts assembled preparatory to the forming of the seam for joining the same, and

Fig. 4 is a view similar to Fig. 3, but showing the seam completed.

In Figures 3 and 4 of the drawing, I have shown a portion of the can end at l which is joined to a can body indicated at 5. The can body is formed with a flange 6 in the usual manner, and the-can end is provided with a peripheral channel portion 8 to which has been applied a plastic coating material indicated at 9. In Fig. 4 of the drawing, the metal parts are rolled into 5 a seam, and the plastic sealing material fills all voids and spaces formed by irregularities in the metal so that the joint is an hermetically sealed joint. This is a well-known type of joint and further description of the same is not necessary.

59 The coating material used in a seam of the above type may be of any approved composition having the quality of deformability or plasticity, so that when the seam is completed by the rolling of the parts, the coating material will efiecu tually fill all voids and spaces caused by the irregularity of the metal and thus produce a sealed Joint.

The present invention has to do with a method of applying the coating to the can end. In the drawing, a can end is illustrated which has par- 6 allel sides and ends with rounded corners. A great deal of difllculty has been experienced in coating a can end of this type. The usual method is to cause a coating nozzle to travel in a path conforming to the channel in the can end for 10 supplying the coating material therto. The irregularity of the path reduces the speed of the machine and the eiliciency of the application of the coating to a certain extent. According to the present method, the coating is applied to the can 5 end by an applicator which rotates and is brought progressively into contact with the can end so as to apply the coatingto the flanged portion or channel of the can end.

In the apparatus illustrated for carrying out 0 the method, there is shown a guideway II for supplying the can ends and for guiding them as they are moved along in a predetermined path, which as illustrated, is a rectilinear path. The movement of the can ends along the guidin channel is accomplished by a conveyor chain I2 equipped with suitably spaced lugs l3 which contact with the can end and pushes the same along the guiding channel. The coating material which is to be applied to the can end is placed in a tank 3 indicated at 15. The coating material is indicated at I6. This tank is located directly beneath the guideway II, and the rails of the guidew are cut out as indicated at It in the drawin so as to provide an opening over which the ca end travels. The opening is so dimensioned that as the can end travels over the same, the channel will be progressively exposed so that an applicator may contact with the under side of the channel. The applicator, as illustrated, is in the form of a roller ll. This roller is engraved or otherwise formed on its periphery with an applicator rib l8, which rib in its development conforms to the channel in the can end. The roller is rotated by suitable means which also operates to move the conveyor so that the two are accurately timed whereby the driving lug It will present the can end with its channel 8 positioned for progressively registering with and contacting with the applicator rib l8. The roller is 5 so disposed relative to the bath of coating material in the tank ii that the surface of the applicator rib passes beneath the surface of the coating material. The coating material will adhere to the applicator rib and form a layer of coating material thereon. A doctor I9 is positioned a slight distance away from the circumferential surface of the rib l8 and will strip excess coatingmaterlalfromtheribleavin'gafllm of uniform thickness of coating material adhering to the can end so as to provide the necessary sealing gasket for sealing the joint as described above.

15 As the applicator continues its rotation, the can end continues its movement and progressively the applicator rib will contact with the forward curved portions of the channel, then the side portions of-the channel, then the rear curved porgo tions of the channel, and finally the rear side portion of the channel in the can end, as viewed in Fig. 2 wherein the arrows indicate the direction of travel of the'can end and the direction of rotation of the applicator. It will thus be seen 25 that by my improved method of coating, the can end travels continuously and is brought into register with the applicator rib, which in a sense, travels with the can endwhile it is applying the coating to the channel of the can end. However,

: a different portion of the applicator rib contacts with the can end so that the applicator rib rolls into the channel at the front side of the can end and then along the channel and out of the channel at the rear side of the can end. While the method is shown as applied to the coating of a so-called square can end, it is understood that it can be applied to round can ends, oval can ends, and can ends of any shape. The applicator, in each instance, is shaped to conform to the channel which is to be coated so that it will make progressive contact therewith as the can end travels across the same. It will be noted that the guideway ll of the can end is so con.- structed that the can end is held in a fixed path of travel and restrained against upward movement when the coating material is being applied 5 thereto. The periodic progressive contact of the can ends with the applicatorrib is characterized as a progressive rolling contact, for the reason that the can end travels in a rectilinear line rela- V tive to the applicator and the applicator roller 1 turns, makes contact with the traveling end and progressively changes the point of contact, finally leavingthe rear end of the can end as it is.

travelingu 7 It is obvious that the method is not limited 1 to the particular apparatus shown and described, but may be carried out in various other ways.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent, isv The method of coating with sealing compound can ends having a channel at the peripheral edge thereof which is irregular in contour relative'to the center of the can end, consisting in moving the can end during coating in a path lying in a 25 plane parallel with and above the surface of a sealing compound coating bath, causing an applicator located between the bath and the can end and having a radially projecting coating rib on the surface thereof conforming in shape to N the channel in the can end, to rotate ab ut an axis parallel to said plane and at right angles to the direction of travel of the end, said applicator being disposed and timed so that the coating rib makes rolling contact with the surface 85 within the channel of the can end to be coated, and also makes contact with'the bath whereby sealing compound is lifted from the bath and applied within the channel of the can end.

ALFRED L. KRONQUEST. 

